{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-74571",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-08-15T05:44:03.917Z",
        "datePublished": "2026-08-15T12:28:10.711Z",
        "dateUpdated": "2026-10-15T10:09:18.278Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-10-15T10:09:18.278Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: skip global block reserve accounting for rescue mounts\n\n[BUG]\nMounting with rescue=ibadroots after corrupting the block group tree\nroot triggers a NULL pointer dereference:\n\n  BUG: kernel NULL pointer dereference, address: 0000000000000100\n  RIP: 0010:btrfs_update_global_block_rsv+0x9d/0x1c0 [btrfs]\n  Call Trace:\n   fill_dummy_bgs+0xd4/0x120 [btrfs]\n   open_ctree+0xc6e/0x1ca0 [btrfs]\n   btrfs_get_tree+0x50d/0xa40 [btrfs]\n\nThe same crash occurs with a corrupted raid stripe tree root, via\nbtrfs_read_block_groups() instead of fill_dummy_bgs().\n\n[CAUSE]\nWith rescue=ibadroots, btrfs_read_roots() allows the mount to continue\nwhen either root cannot be read, leaving the corresponding root pointer\nNULL while its on-disk feature bit remains set.\n\nbtrfs_update_global_block_rsv() then dereferences the missing root based\non the feature bit alone.\n\n[FIX]\nRescue mounts are fully read-only and cannot start transactions, so the\nglobal reserve is never consumed. Under btrfs_is_full_ro(), mark the\nreserve as full and return before performing the accounting.\n\nAnd since we need to check if the fs is mount fully RO, export\nfs_is_full_ro() as btrfs_is_full_ro(), and move it to fs.h.\n\n[ Squash the fs_is_full_ro() export commit into this one. ]"
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "fs/btrfs/block-rsv.c",
                        "fs/btrfs/disk-io.c",
                        "fs/btrfs/fs.h"
                    ],
                    "versions": [
                        {
                            "version": "8dbfc14fc736eb701089aff09645c3d4ad3decb1",
                            "lessThan": "969a96479add6bd42d7f7241f99f27b31571a953",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "8dbfc14fc736eb701089aff09645c3d4ad3decb1",
                            "lessThan": "076349e4c8d11f6b58c4549976a513b2b4dc6df2",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "8dbfc14fc736eb701089aff09645c3d4ad3decb1",
                            "lessThan": "51a0e8399858621442807a26057bcd1cd3ced046",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "cbec34d3021d47007a0334c634f7053dbaf93d02",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "1e8087589b5cf6fa17adaf57b64cf1656d77dfec",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "6.1.43",
                            "lessThan": "6.2",
                            "status": "affected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.4.8",
                            "lessThan": "6.5",
                            "status": "affected",
                            "versionType": "semver"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "fs/btrfs/block-rsv.c",
                        "fs/btrfs/disk-io.c",
                        "fs/btrfs/fs.h"
                    ],
                    "versions": [
                        {
                            "version": "6.5",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.5",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.57",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.1.8",
                            "lessThanOrEqual": "7.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.5",
                                    "versionEndExcluding": "6.18.57"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.5",
                                    "versionEndExcluding": "7.1.8"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.5",
                                    "versionEndExcluding": "7.2"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.1.43"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.4.8"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/969a96479add6bd42d7f7241f99f27b31571a953"
                },
                {
                    "url": "https://git.kernel.org/stable/c/076349e4c8d11f6b58c4549976a513b2b4dc6df2"
                },
                {
                    "url": "https://git.kernel.org/stable/c/51a0e8399858621442807a26057bcd1cd3ced046"
                }
            ],
            "title": "btrfs: skip global block reserve accounting for rescue mounts",
            "x_generator": {
                "engine": "bippy-1.2.0"
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}